Aligning a GSM antenna

Calahonda52

How should this antenna be aligned?
I know where the nearest masts are and I plan to have the antenna as high as possible.

Should it point at the mast or should it be at right angles?
Should the arms be vertical or horizontal?
Thanks

ps
found an app called Antenna Pointer which seems to do the directional bit

Looks like arms should be vertical

Calahonda52

Just to add to this:
The first app needed a compass in fone which I font have, but it showed me all the masts nearby, like the Comreg site.
Another app picks out the masts by carrier.
I am on 3 and it seems the nearest 3 mast is 4 km away, and that is what the app locks onto rather than the nearest one at 1km away.
The 3 mast is the one Google uses to track my location if I turn on location and dont move from house.
I thought madts were shared?
Any thoughts pls?

Max Power 2010

Only thought I can say is stop what your doing, I work in the industry and technically what your doing is repeating your nearest cell site on the network and even if done correctly causes a lot of issues for anyone else in your area.

as the cell ID is duplicated the network would struggle to route calls to customers and most calls would drop for anyone using that site.

the legalities are well documented on boards, so not going to mention that, but it's best you deal with your operator for coverage problems, they may be able to provide a solution as a repeater would need it's own cell id if was to work.

Calahonda52

I am extending a passive antenna from an GSM modem on an alarm box.

The operator doesn't want to know as we don't spend enough, they want a monthly bill of c 150-200 pre VAT before they will even stop yawning.

Max Power 2010

ok sorry my fault, completely misunderstood what the Antenna was for, got carried away there, thought it was a gsm repeater.

yep, as high as you can really without putting yourself out, Vertical Pol is your best bet.